Footwear with heavy sole parts



Feb. 28, 1967 A. s. J. KALSOY 3,305,947

FOOTWEAR WITH HEAVY SOLE PARTS Filed Oct. 4, 1963 v 2 Sheets-Sheet 1 INVENT OR ANNE SKY. KALsoY ATTORNEYS Feb. 28, 1967 A. s. J. KALsoY 3,305,947

FOOTWEAR WITH HEAVY SOLE PARTS Filed Oct. 4, 1963 2 Sheets-Sheet 2 INVENTOR ANNE S. J- KALsoY m$flwwimwm ATTORNEYS United States Patent 3,305,947 FOOTWEAR WITH HEAVY SOLE PARTS Anne Sofie Julie Kalsoy, Bredzade 12, Copenhagen, Denmark Filed Oct. 4, 1963, Ser. No. 314,034 Claims priority, application Switzerland, Oct. 6, 1962,

5 Claims. (Cl. 36-25) The present invention relates to footwear of the kind having heavy sole parts formed in such manner that when the user is walking the footwear is rocking or rolling on a curved surface located on the underside of the sole and beneath the ball of the foot.

The object of the invention is to give the footwear such form that the foot is tired less on walking and standing than is the case of the many existing forms of footwear, regardless whether they be boots, shoes, sandals, wooden shoes or other footwear.

There are many known shoes and sandals which are adapted to the different requirements for the support of the foot. This is usually accomplished by forming the supporting surface for the foot in suitable manner.

Such footwear, however, has the drawback that the heel is turned outwardly as the foot is treading on the sole, which involves an unfavourable movement of the leg and the knee. The known soles are often provided with a support for the whole arch of the foot, and the said support is also maintained when the muscles of the foot at the arch are tightened. The said supports, which consist in substantially raised sections on the upper side of the sole, certainly support the foot, but they prevent the muscles from working freely and consequently render necessary strengthening of the musculature impossible.

The invention is concerned with footwear which is better adapted to normal walking of a human person and whichallows the footwear to be worn the whole day, just as it prevents the toe of the treading foot from swinging outwards in relation to the heel. Since the big toe is the most powerful of the toes it is advantageous to transfer the main weight of the body on this toe when taking off from the floor. The footwear is formed in such manner that the way of treading performed by primitive people moving on soft ground can be adopted by people who have always to walk on a hard, fiat surface. By means of the footwear according to the invention a normal movement of the leg is supported and abnormal walking as frequently seen with children is eliminated.

Much pain in the muscles of the back and the legs may be ascribed to an abnormal movement of the leg during walking and a normal tread of the foot on its supporting surface. By a health-improving movement of the leg and a suitable tread it will be possible to relieve much pain through the use of footwear according to the invention, and the muscles of foot and leg will be strengthened.

The footwear according to the invention is characterised in that the aforesaid curved surface extends from a rectilinear generatrix which emanates from a point lying beneath the rear part of the location of the treading surface of the little toe and is directed obliquely rearwards, forming an angle of about 7090 with a connecting line which extends from the point of the extreme part of the big toe and to the point of the rear part of the outer side of the heel, the said surface curving upwards in the direction towards the location of the big toe and the said angle being measured from the location of the big toe and towards the outer side of the foot.

By this form of footwear the foot is, during walking, caused to shift the pressure on the ball of the foot onto the treading surface of the big toe instead of on the treading surface of the remaining four toes; this gives a safer and less tiring walk because the big toe owing to its strength is comfortable to take off with when walking.

The said effect may according to the invention be im proved thereby so that the said curved surface is formed as a cylindrical surface, preferably a right circular cylindrical surface embodying the aforesaid generatrix.

The strength of the big toe may even be further utilised in a take-01f if by another embodiment of the foot-wear according to the invention the curved surface is designed as a developable, for example as a conical surface, which, compared with a cylindrical surface, will curve more upwardly in the side of the big toe than in the side of the little toe.

A very long tread and consequently a very healthy walking are obtained if in the further embodiment of the footwear according to the invention the tangential plane of the curved surface in the said generatrix is lying closer to the supporting surface of the users foot than to the generatrix.

To ensure a suitable and uniform transfer of the pressure of the foot from the heel to the ball of the foot before the pressure is re-transferred uniformly therefrom to the treading surface of the big toe, the footwear according to the invention may have a slight depression formed in the supporting surface for the foot and having its outer heel section lying somewhat deeper than the inner heel section and curving slightly from the heel section along the outer side of the sole in the direction towards the treading surface of the little toe, from which it rises slightly in forward direction, whereas in the area as the ball of the foot it is curving substantially more inwardly and rising somewhat inwardly in the said area, whereas the surface supporting the four small toes is rising somewhat more in relation to the depression in addition to which the big toe has a treading surface which declines strongly in the direction of the toe, a raised section provided beneath the arch of the foot rising from the surrounding depression with a gentle transition, the said raised section continuing rearwardly and towards the inner side of the footwear in a raised section the surface of which supports the arch beneath about the rearmost one-third of same and rises strongly from the heel section, all of it in such manner that the foot, when treading on the heel, is slightly supported at the arch and is caused to rest with its outer part in the depression, whereby it heels slightly outwards and subsequently at the transfer of the weight forwardly treads along a slightly curved line in the direction towards the little toe and subsequently, when the rear part of the sole is lifted, treads along a continuous, more curved arch in the direction towards the big toe, whereby the foot receives an inward inclination simultaneously with the sole treading on the curved surface beneath the big toe, whereby the foot is raised more at its rear outer part and the knee cannot move outwards, so that the big toe will be carrying the main weight of the body.

Other details and modifications of the footwear according to the invention will be described in the following in connection with one embodiment of the footwear.

In the drawings:

FIGURE 1 is a perspective view of a sole for the left foot, viewed obliquely from below,

FIGURE 2 shows a sole for the left foot, viewed from below,

FIGURE 3 shows a sole with markings for the supporting surface for a left foot,

FIGURE 4 is a cross-sectional view taken along line 4-4 in FIGURE 3, and

FIGURE 5 is an elevational view of the side illustrated in FIGURE 1.

The disclosed footwear 1 consists substantially of a sole 2. Such parts of the underside of the sole as contact the support have a heel section 3 and a front section 4. The parts 3 and 4 may be located in the same plane, but this is not necessary and they need not even be planular plane any of them. The front section 4 passes at a line F into a surface 5 which rises in the direction of the extreme end of the big toe and the line F forms an angle at of about 70-90 with a line A which connects the outer heel section with the extreme end of the big we as indicated in FIGURES 2 and 3, the said angle being measured from the point of the toe towards the outer side of the footwear. The line F begins at the outer side of the footwear at a place lying beneath the rear end of the treading surface of the little toe.

On the surface 5 the tread of the sol-e on the support proceeds in such a manner that the rearmost outer part of the sole is raised more than the inner part of same. As a result, the knee of the user of the footwear will not bend outwards when he is walking, which would involve an injurious movement of the muscles of leg and body.

The underside of the sole is provided with a recess 6 which serves to increase the elasticity of the sole in the event that it consists of an elastic material and furthermore it reduces the weight of the sole.

On its upper side the sole has a supporting surface 7 in which there is a slight depression -8. The rear part of the said depression is adapted to suit the form of the heel and the inner section 81 of the depression is slightly less deep than its outer section 82. The depression 8 extends forwardly in a slight curve, indicated by a line M1 in FIGURE 3 in the direction of the treading surface of the little toe, and the depression rises slightly forwardly from the outer heel section 82, form ing an angle of 57, after which the depression continues as an increased curvature, indicated by the line M2 in FIGURE 3, towards the treading surface of the big toe, after which the depression is fading out.

The surface 9, on which the four smaller toes are resting rises in forward direction from the slight depression 8, forming an angle of about 1-30.

The big toe is supported by a surface 10 which is inclining about 810 downwards in the direction towards the point of the toe.

Behind the treading surfaces of the smaller toes is provided a slightly raised section 11 located beneath the ball of the foot. The said raised section 11 rises to about 1-2 mm. above the deepest places of the surrounding depression. All transitions between the depression and the raised section are uniform and gentle so as to provide a supporting surface that is very gentle beneath the front part of the foot and inclines slightly inwards, whereas as mentioned heel sections are inclining slightly outwards. At its rear end the raised section 11 passes gently into a more pronounced raised section 12 for the arch of the foot. The said raised section 12 has a surface which supports the arch of the foot, though only about the rearmost one-third of same. The raised section 12 rises compartively abruptly from the inner heel section 81 to support the desired outwardly directed inclination of the heel section. The raised section 12 is only supporting the tarsus, not the arch of the foot.

The sole is attached to the foot in suitable manner and may, for example, be made of wood and be provided with wearing surfaces of rubber or plastic, but it may also as a whole be made of an elastic material such as cork, rubber, leather or an elastic plastic material.

By the aforesaid design of the supporting surface for the foot and the underside of the sole the following movement of the foot is produced in walking: The user puts the footwear with the heal against the ground so that both of the parts 3 and 4 are resting against same, but the main weight of the body is transferred through the heel. This will cause the foot and the leg to incline slightly outwards whereby the heel and the extreme part of the foot will arrange themselves in the depression 4 8. The outer part of the foot is located in the front area, slightly raised. The rear part of the arch of the foot is supported by the raised section 12. The muscles in the arch may thereby move freely, which is useful for strengthening these muscles.

By the said design of the supporting surface for the foot the foot is pressed into the depression 8, on which the tread of the outer part proceeds until the weight of the body rests on the arch of the foot, after which the tread proceeds from the ball of the foot in the direction towards the big toe. Simultaneously, the sole rocks or rolls on the curved surface 5 as soon as the weight has been transferred to the ball of the foot, and owing to the rolling of the sole on the surface 5 of the support the foot is forced to lift itself more on the outer side rearwardly so that the leg is consequently guided in such manner that the knee is moved straightly in forward direction. Anyway the knee is prevented from moving outwardly. The big toe will thus gradually be subjected to the main weight of the entire body, 'but owing to its more powerful nature the said toe is also capable of receiving this weight without being tired, and the big toe also transfers the desired main force at the take-off of the foot from the support.

Tests and experiments have clearly shown that by this movement the muscles of the body are acted upon in advantageous manner and that there is no tendency to deformity of the toes such as hammertoes. Any tendency to deformation of feet or muscles will, as a rule, rapidly cease so that the movement described permits a perma nent use of the footwear according to the invention.

The sole 2 may be attached to the foot by means of straps so that the foot may breathe freely. For this purpose the sole has at least one through-going opening 13 through which a strap may be passed.

What I claim and desire to secure by Letters Patent is:

1. A footwear having a sole structure comprising a member having a bottom surface and .a foot supporting top surface, said top surface having forwardly disposed little toe and big toe supporting surface portions, a rearwardly disposed heel supporting surface portion, and intermediately disposed ball and arch supporting surface portions, said bottom surface having an upwardly and forwardly curved surface portion extending toward the big toe supporting portion of said member, said curved surface portion emanating from a rectilinear line lying at an angle in the range of 70 to to a rectilinear line intersecting the forwardmost point of the big toe supporting portion of said member and a rear point of the heel supporting portion of said member, and passing through a point on the little toe supporting portion of said member, the radius of curvature of said curved surface portion increasing in a direction from the big toe supporting portion to the little toe supporting portion of said member to provide a substantially conically shaped curved surface portion, and the thickness of the ball supporting portion of said member being greater than the thickness of the heel supporting portion of said member.

2. A footwear having a sole structure comprising a member having a bottom surface and a foot supporting top surface, said top surface having forwardly disposed little toe and big toe supporting surface portions, a rearwardly disposed heel supporting surface portion, and intermediately disposed ball and arch supporting surface portions, said bottom surface having an upwardly and forwardly curved surface portion extending toward the big tge supporting portion of said member, said curved surface portion emanating from a rectilinear line lying at an angle in the range of 70 to 90 to a rectilinear line intersecting the forwardmost point of the big toe supporting portion of said member and a rear point of the heel supporting portion of said member, and passing through a point on the little toe supporting portion of said member, and said top surface having a shallow curved depression extending from the heel support portion, forwardly, outwardly of the arch supporting surface portion, and inwardly adjacent and rearwardly of the ball supporting surface portion, the rear portion of said depression having the outer portion thereof depressed deeper than the inner portion thereof and curved forwardly and upwardly toward the little toe supporting surface portion, wherefrom it slopes gradually upwardly and forwardly merging with said little toe supporting portion which continues to slope gradually upwardly and forwardly, the portion of said depression disposed adjacent said ball supporting surface portion sloping gradually upwardly, said big toe supporting surface portion sloping downwardly and forwardly, said arch supporting surface portion being elevated and merging gradually with said depression, the rearward end of said arch supporting surface portion which supports the rearmost one-third of the arch of the foot, being elevated slightly higher than the remaining part of said arch supporting surface portion and sloping downwardly and rearwardly to merge with said heel supporting surface portion whereby the foot when treading on the heel supporting surface portion is supported slightly by the arch supporting surface portion and at its outer side in said depression, causing the foot to heel slightly outwardly, when the weight on the foot is transferred forwardly the foot treads in said depression in a slightly curved line toward the little toe supporting surface portion, when the rear part of the member is lifted the foot continues to tread along said depression in a more curved line toward the big toe supporting surface portion, the foot receives an inward inclination simultaneously when said member treads on said curved bottom surface portion, causing the rear end of the foot to be lifted, preventing the knee of the user to move outwardly and causing the big toe of the user to carry the principal weight of the user.

3. A footwear having a sole structure according to claim 2, wherein said depression slopes upwardly from said heel supporting portion toward said little toe supporting portion at an angle in the range of 5 to 7".

4. A footwear having a sole structure according to claim 3, wherein the supporting surface for the four small toes slopes upwardly and forwardly at an angle in the range of 1 to 3.

5. A footwear having a sole structure according to claim 4, wherein the big toe supporting surface slopes downwardly and forwardly at an angle in the range of 8 to 10.

References Cited by the Examiner UNITED STATES PATENTS 1,851,778 3/1932 Skillen 367.5 2,847,769 8/ 1958 Schlesinger 36--107 FOREIGN PATENTS 311,980 5/1918 Germany. 673,456 3/1939 Germany. 968,858 4/ 1958 Germany. 644,815 10/ 1950 Great Britain.

PATRICK D. LAWSON, Primary Examiner. 

1. A FOOTWEAR HAVING A SOLE STRUCTURE COMPRISING A MEMBER HAVING A BOTTOM SURFACE AND A FOOT SUPPORTING TOP SURFACE, SAID TOP SURFACE HAVING FORWARDLY DISPOSED LITTLE TOE AND BIG TOE SUPPORTING SURFACE PORTIONS, A REARWARDLY DISPOSED HEEL SUPPORTING SURFACE PORTION, AND INTERMEDIATELY DISPOSED BALL AND ARCH SUPPORTING SURFACE PORTIONS, SAID BOTTOM SURFACE HAVING AN UPWARDLY AND FORWARDLY CURVED SURFACE PORTION EXTENDING TOWARD THE BIG TOE SUPPORTING PORTION OF SAID MEMBER, SAID CURVED SURFACE PORTION EMANATING FROM A RECTILINEAR LINE LYING AT AN ANGLE IN THE RANGE OF 70* TO 90* TO A RECTILINEAR LINE INTERSECTING THE FORWARDMOST POINT OF THE BIG TOE SUPPORTING PORTION OF SAID MEMBER AND A REAR POINT OF THE HEEL SUPPORTING PORTION OF SAID MEMBER, AND PASSING THROUGH A POINT ON THE LITTLE TOE SUPPORTING PORTION OF SAID MEMBER, THE RADIUS OF CURVATURE OF SAID CURVED SURFACE PORTION INCREASING IN A DIRECTION FROM THE BIG TOE SUPPORTING PORTION TO THE LITTLE TOE SUPPORTING PORTION OF SAID MEMBER TO PROVIDE A SUBSTANTIALLY CONICALLY SHAPED CURVED SURFACE PORTION, AND THE THICKNESS OF THE BALL SUPPORTING PORTION OF SAID MEMBER BEING GREATER THAN THE THICKNESS OF THE HEEL SUPPORTING PORTION OF SAID MEMBER. 